The goal of this proposal is to investigate the role of visual area V4 in representation of and attention towards different features in the visual scene, such as contour, color/brightness, and depth, features that ultimately lead to processing and recognition of form. While in other early visual areas such as area V2, these features are represented in distinct organizations. However, due to the complexity of this area, the functional organization of area V4 has been elusive. To provide a better understanding of the functional architecture underlying form recognition and visual attention, we propose to use optical imaging, voltage sensitive dye imaging, single unit recording, and anatomical tracing methods. These experiments will elucidate the neural circuitries underlying visual behavior and attention, understanding that will have clinical relevance for, for example, attention deficit disorder and epilepsy. PUBLIC HEALTH RELEVANCE: The goal of this proposal is to investigate the functional organization of visual area V4 in the primate cerebral cortex. This is an area involved in form perception and visual attention. We will study how the organization of area V4 relates to form perception and attention. Organizations underlying spatial and featural attention will be examined. These studies will elucidate the neural circuitries underlying visual behavior and attention, understanding that will have clinical relevance for conditions such as cortical strokes, attention deficit disorder, and schizophrenia.